We compared the results of 1-stage uncemented bilateral total hip arthroplasty (THA) performed in 49 patients (98 hips) with those of 2-stage uncemented bilateral THA performed during the same hospital stay in 40 patients (80 hips). There was no significant difference in mean Harris Hip Score preoperatively and at final follow-up between the 2 groups. Radiographic evaluation of patients in the 1-stage group revealed the acetabular component was stable in 95 hips and possibly unstable in 3. The femoral component was bone-ingrown in 91 hips and stable fibrous in 7. In the 2-stage group, the acetabular component was stable in 77 hips and possibly unstable in 3. The femoral component was bone-ingrown in 71 hips and stable fibrous in 9. In both groups, no patients exhibited clear signs of loosening, migration or osteolysis.In the 1-stage group, postoperative dislocation occurred in 2 hips and 1 patient had developed deep venous thrombosis and pulmonary embolism. In the 2-stage group, no complications were observed. The incidence of complications was not significantly different between the 2 groups.There was no significant difference in the total blood loss and mean hemoglobin level preoperatively and at discharge between the 2 groups. However, in the 1-stage group, operative time, intraoperative blood loss, procedure cost, and hospital stay were significantly reduced compared with the 2-stage group. Therefore, 1-stage bilateral THA is a safe and effective option for patients with significant arthritic disease of both hips.